APPENDIX
II SOUTHERN JOURNEY DISTANCES BY THE COMMANDER OF THE EXPEDITION The following
Table gives detailed
information regarding the distances travelled day by day on the
Southern
Journey. The number of
geographical miles
given in the first column covers the period from November 15, 1908, to
January
9, 1909. The distances have been taken from the chart after all
corrections
have been made, and represent a direct line from camp to camp. In the second
column will be found
the noon latitudes, calculated from observations taken as opportunity
offered. The last column
shows the distances
travelled day by day according to sledge-meter, and these figures take
into
account all deviations and detours so often rendered necessary by the
condition
of the surface. The reliability of the sledge-meter is proved by the
fact that
on the homeward journey we were able to determine our positions without
taking
latitude observations. Only one observation was taken on the return
journey
(January 31, 1909), and on that occasion the theodolite confirmed the
record of
the sledge-meter. The latitude
observations noted in
this Table were taken with a three-inch theodolite, which was carefully
adjusted before the start for the southern journey. An observation
taken on the
return journey, in February, when the position was known from bearings,
showed
that the instrument was correct. The observations were only taken with
the
theodolite "face left," but as the instrument was in good adjustment
this was sufficient. On the outward
journey the last
latitude observation was taken in latitude 87° 22' South. The remainder
of the
distance marched towards the south was calculated by sledge-meter and
dead
reckoning. The accuracy of the sledge-meters used was proved by the
fact that
on the return journey we were able to pick up the depots without taking
observations. The "slip" was ascertained by careful tests before the
start of the journey. The chronometer
watches taken were
rated before leaving and on the return, and the error was only eight
seconds.
All bearings, angles, and azimuths were taken with the theodolite.
Variation
was ascertained by means of a compass attached to the theodolite, and
the
steering compasses were checked accordingly. At noon each day the
prismatic
compasses were placed in the true meridian, and checked against the
theodolite
compass and the steering compasses.
The total
distance marched, from
October 29 to March 4, as recorded on the sledge-meters, was 1755 miles
209
yards statute, this including relay work and back marches. |